Autonomous transport vehicle charging system

ABSTRACT

A charging system for autonomous transport vehicles including at least one charging contact disposed on each pick floor level of a storage and retrieval system, each of the at least one charging contact being located at a transfer station, at least one power supply configured to supply power to the at least one charging contact, and a controller in communication with the transfer station and being configured to communicate information relating to a transfer of items between the transfer station and a predetermined one of the autonomous transport vehicles and to apply power from the power supply to the at least one charging contact for charging the predetermined autonomous transport vehicle corresponding to the transfer and located at the transfer station, wherein the controller is configured to supply power to the charging contacts simultaneously with the predetermined autonomous transport vehicle exchanging items related to the transfer at the transfer station.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. Non-Provisional patentapplication Ser. No. 15/702,474, filed on Sep. 12, 2017 (now U.S. Pat.No. 10,207,595), which is a continuation of U.S. Non-Provisional patentapplication Ser. No. 15/359,366, filed on Nov. 22, 2016 (now U.S. Pat.No. 9,758,049), which is a continuation of U.S. Non-Provisional patentapplication Ser. No. 14/799,367, filed on Jul. 14, 2015 (now U.S. Pat.No. 9,499,062), which is a continuation of U.S. Non-Provisional patentapplication Ser. No. 13/326,823, filed on Dec. 15, 2011 (now U.S. Pat.No. 9,082,112) which claims the benefit of and priority from U.S.Provisional Patent Application No. 61/423,402, filed on Dec. 15, 2010,the disclosures of which are incorporated herein by reference in theirentireties.

BACKGROUND 1. Field

The embodiments generally relate to storage and retrieval systems and,more particularly, to autonomous transports of the storage and retrievalsystems.

2. Brief Description of Related Developments

Warehouses for storing case units may generally comprise a series ofstorage racks that are accessible by transport devices such as, forexample, fork lifts, carts and elevators that are movable within aislesbetween or along the storage racks or by other lifting and transportingdevices. These transport devices may be automated or manually driven.Generally the items transported to/from and stored on the storage racksare contained in carriers, for example storage containers such as trays,totes or shipping cases, or on pallets.

It would be advantageous for the automated transport vehicle to operateat substantially full utility while transporting items throughout thestorage and retrieval system.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing aspects and other features of the disclosed embodimentsare explained in the following description, taken in connection with theaccompanying drawings, wherein:

FIG. 1 schematically illustrates an exemplary storage and retrievalsystem in accordance with the embodiments;

FIG. 2A illustrates a schematic view of a portion of the storage andretrieval system of FIG. 1 in accordance with the embodiments;

FIG. 2B is another schematic illustration of a portion of the storageand retrieval system of FIG. 1 in accordance with the embodiments;

FIG. 3 illustrates a schematic view of a portion of an autonomoustransport vehicle charging system in accordance with the embodiments;

FIG. 4 illustrates an exemplary graph of an autonomous transport vehiclecharging cycle in accordance with the embodiments;

FIG. 5 is a schematic illustration of an exemplary topology for anautonomous transport vehicle charging system in accordance with theembodiments;

FIG. 6 is a schematic representation of service interactions for anautonomous transport vehicle charging system in accordance with theembodiments;

FIG. 7 is a schematic illustration of an autonomous transport vehiclecharging sequence in accordance with the embodiments;

FIG. 8 is an illustration of an exemplary charger state diagram inaccordance with the embodiments;

FIG. 9 is a schematic illustration of a portion of a communicationhierarchy for an autonomous transport vehicle charging system inaccordance with the embodiments;

FIG. 10 illustrates a schematic view of a portion of a storage andretrieval system in accordance with the embodiments;

FIG. 11 illustrates a schematic waypoint list for an autonomoustransport vehicle in accordance with the embodiments;

FIG. 12 illustrates an exemplary schematic state chart diagram for aportion of an autonomous transport vehicle charging system in accordancewith the embodiments; and

FIG. 13 is a schematic illustration of an exemplary sequence diagram forcharging transactions of an autonomous transport vehicle charging systemin accordance with the embodiments.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENT(S)

FIG. 1 schematically illustrates an exemplary storage and retrievalsystem 100 in accordance with the embodiments. Although the disclosedembodiments will be described with reference to the embodiments shown inthe drawings, it should be understood that the disclosed embodiments canbe embodied in many alternate forms. In addition, any suitable size,shape or type of elements or materials could be used.

In accordance with the embodiments the storage and retrieval system 100may operate in a retail distribution center or warehouse to, forexample, fulfill orders received from retail stores for case units(where case units as used herein means items not stored in trays, ontotes or on pallets, e.g. uncontained or items stored in trays totes oron pallets). It is noted that the case units may include cases of items(e.g. case of soup cans, boxes of cereal, etc.) or individual items thatare adapted to be taken off of or placed on a pallet. In accordance withthe embodiments, shipping cases or case units (e.g. cartons, barrels,boxes, crates, jugs, totes, pallets or any other suitable device forholding case units) may have variable sizes and may be used to holditems in shipping and may be configured so they are capable of beingpalletized for shipping. It is noted that when, for example, bundles orpallets of case units arrive at the storage and retrieval system thecontent of each pallet may be uniform (e.g. each pallet holds apredetermined number of the same item—one pallet holds soup and anotherpallet holds cereal) and as pallets leave the storage and retrievalsystem the pallets may contain any suitable number and combination ofdifferent items (e.g. each pallet may hold different types of items—apallet holds a combination of soup and cereal). In the embodiments thestorage and retrieval system described herein may be applied to anyenvironment in which case units are stored and retrieved.

The storage and retrieval system 100 may be configured for installationin, for example, existing warehouse structures or adapted to newwarehouse structures. In the embodiments, the storage and retrievalsystem may include in-feed and out-feed transfer stations 170, 160,multilevel vertical conveyors 150A, 150B, autonomous transport vehicleor robot (referred to herein as “bots”) stations 140A, 140B, a storagestructure 130, and a number of bots 110. Suitable examples of storageand retrieval systems may be found in U.S. patent application Ser. No.12/757,220, entitled “STORAGE AND RETRIEVAL SYSTEM” and filed on Apr. 9,2010 and U.S. patent application Ser. No. 12/757,381, entitled “STORAGEAND RETRIEVAL SYSTEM” and filed on Apr. 9, 2010, and U.S. ProvisionalPatent Application Ser. No. 61/423,340 entitled “Warehousing ScalableStorage Structure” filed on Dec. 15, 2010 (now U.S. patent applicationSer. No. 13/326,674 filed on Dec. 15, 2011), the disclosures of whichare incorporated by reference herein in their entireties. The in-feedtransfer stations 170 and out-feed transfer stations 160 may operatetogether with their respective multilevel vertical conveyors 150A, 150Bfor bi-directionally transferring case units to and from one or morelevels of the storage structure 130. It is noted that while themultilevel vertical conveyors 150 are described herein as beingdedicated inbound or in-feed conveyors 150A and outbound or out-feedconveyors 150B, each of the conveyors 150A, 150B may be used for bothinbound and outbound transfer of case units/items from the storage andretrieval system. The multilevel vertical conveyors 150 may be anysuitable lifting devices for transporting case units between levels ofthe storage and retrieval system. Some non-limiting suitable examples ofmultilevel vertical conveyors can be found in, for example, U.S.Provisional Patent Application No. 61/423,298, entitled “MULTILEVELVERTICAL CONVEYOR PLATFORM GUIDES” filed on Dec. 15, 2010, and U.S.patent application Ser. No. 12/757,354, entitled “LIFT INTERFACE FORSTORAGE AND RETRIEVAL SYSTEMS” and filed on Apr. 9, 2010 (thedisclosures of which are incorporated by reference herein in theirentireties) and U.S. patent application Ser. No. 12/757,220, entitled“STORAGE AND RETRIEVAL SYSTEM,” (previously incorporated by reference).For example, the multilevel vertical conveyors 150A, 150B may have anysuitable number of support shelves 250 (FIG. 2) for transporting thecase units to a predetermined level 261-264 (FIG. 2) of the storage andretrieval system 100. The support shelves 250 may have slatted supportsconfigured to allow, for example, fingers of a transfer arm 110A (FIGS.2A, 2B) of the bots 110 to pass between the slats for transferring caseunits 101 (FIG. 2) to and from the conveyor. In alternate embodiments,case units may be indirectly transferred between the bots 110 and themultilevel vertical conveyors 150A, 150B as described in, for example,U.S. patent application Ser. No. 12/757,220, entitled “STORAGE ANDRETRIEVAL SYSTEM,” (previously incorporated by reference). It is notedthat in the embodiments transfer of case units between the bots 110 andmultilevel vertical conveyors may occur in any suitable manner.

As may be realized, the storage and retrieval system 100 may includemultiple in-feed and out-feed multilevel vertical conveyors 150A, 150Bthat are accessible by, for example, bots 110 on each level of thestorage and retrieval system 100 so that one or more case unit(s) can betransferred from a multilevel vertical conveyor 150A, 150B to eachstorage space on a respective level and from each storage space to anyone of the multilevel vertical conveyors 150A, 150B on a respectivelevel. The bots 110 may be configured to transfer the case units betweenthe storage spaces on storage racks 600 (FIG. 2B) and the multilevelvertical conveyors with one pick (e.g. substantially directly betweenthe storage spaces and the multilevel vertical conveyors). By way offurther example, the designated bot 110 picks the case unit(s) from ashelf of a multilevel vertical conveyor, transports the case unit(s) toa predetermined storage area of the storage structure 130 and places thecase unit(s) in the predetermined storage area (and vice versa). It isnoted that while multilevel vertical conveyors are described herein inother aspects the conveyors may be any suitable conveyors ortransfer/picking devices having any suitable transport path orientation.

The bots 110 may be configured to place case units, such as the abovedescribed retail merchandise, into picking stock in the one or morelevels of the storage structure 130 and then selectively retrieveordered items for shipping the ordered items to, for example, a store orother suitable location. As described above, the bots 110 may interfacein any suitable manner with the multilevel vertical conveyors 150A, 150Bsuch as through, for example, extension of a transfer arm 110A (FIG. 2A)of the bot (which may have fingers for interfacing with slatted supportshelves of the multi-level vertical conveyors) relative to a frame ofthe bot. In the embodiments the bot may also interface with themultilevel vertical conveyors indirectly in any other suitable manner.Suitable examples of bots are described in U.S. patent application Ser.No. 12/757,312, entitled “AUTONOMOUS TRANSPORTS FOR STORAGE ANDRETRIEVAL SYSTEMS” and filed on Apr. 9, 2010, U.S. Provisional PatentApplication Ser. No. 61/423,220 entitled “BOT PAYLOAD ALIGNMENT ANDSENSING” filed on Dec. 15, 2010 (now U.S. patent application Ser. No.13/327,040 filed on Dec. 15, 2011), U.S. Provisional Patent ApplicationSer. No. 61/423,365 entitled “AUTOMATED BOT WITH TRANSFER ARM” filed onDec. 15, 2010 (now U.S. patent application Ser. No. 13/326,952 filed onDec. 15, 2011), U.S. Provisional Patent Application Ser. No. 61/423,388entitled “AUTOMATED BOT TRANSFER ARM DRIVE SYSTEM” filed on Dec. 15,2010 (now U.S. patent application Ser. No. 13/326,993 filed on Dec. 15,2011), U.S. Provisional Patent Application Ser. No. 61/423,359 entitled“BOT HAVING HIGH SPEED STABILITY” filed on Dec. 15, 2010 (now U.S. Pat.No. 8,965,619 issued on Feb. 24, 2015), and U.S. Provisional PatentApplication Ser. No. 61/423,206 entitled “BOT POSITION SENSING” filed onDec. 15, 2010 (now U.S. patent application Ser. No. 13/327,035 filed onDec. 15, 2011), the disclosures of which are incorporated by referenceherein in their entireties.

The storage structure 130 may include multiple levels of storage rackmodules 600 (FIG. 2B) where each level includes an array of storagespaces (arrayed on the multiple levels and in multiple rows on eachlevel), picking aisles 130A formed between the rows of storage spaces,and transfer decks 130B. In the embodiments, the picking aisles 130A andtransfer decks 130B may be arranged for allowing the bots 110 totraverse respective levels of the storage structure 130 for placing caseunits into picking stock and to retrieve the ordered case units. As maybe realized, the storage and retrieval system may be configured to allowrandom accessibility to the storage spaces. For example, all storagespaces in the storage structure 130 may be treated substantially equallywhen determining which storage spaces are to be used when picking andplacing case units from/to the storage structure 130 such that anystorage space of sufficient size can be used to store items. The storagestructure 130 may also be arranged such that there is no vertical orhorizontal array partitioning of the storage structure. For example,each multilevel vertical conveyor 150A, 150B is common to all storagespaces (e.g. the array of storage spaces) in the storage structure 130such that any bot 110 can access each storage space and any multilevelvertical conveyor 150A, 150B can receive case units from any storagespace on any level so that the multiple levels in the array of storagespaces substantially act as a single level (e.g. no verticalpartitioning). The multilevel vertical conveyors 150A, 150B can alsoreceive case units from any storage space on any level of the storagestructure 130 (e.g. no horizontal partitioning). It is noted that in theembodiments the storage and retrieval system may be configured so thateach multilevel vertical conveyor serves a predetermined area of thearray of storage spaces. Suitable exemplary configurations of storageand retrieval systems can be found in, for example, U.S. patentapplication Ser. No. 12/757,381, entitled “STORAGE AND RETRIEVAL SYSTEM”and filed on Apr. 9, 2010, the disclosure of which is incorporated byreference herein in its entirety.

The storage structure 130 may also include charging stations 290 forreplenishing, for example, a battery pack, capacitor, ultra-capacitor orother electricity storage device of the bots 110 as will be described ingreater detail below. The charging stations 290 may be located at, forexample, bot stations 140A, 140B (generally 140) of the transfer deck130B so that the bots 110 can substantially simultaneously transferitems, for example, to and from a multilevel vertical conveyor 150A,150B while being charged. The bots 110 and other suitable features ofthe storage and retrieval system 100 may be controlled by, for example,one or more central system control computers (e.g. control server) 120through, for example, any suitable network 180. The network 180 may be awired network, a wireless network or a combination of a wireless andwired network using any suitable type and/or number of communicationprotocols. It is noted that, the system control server 120 may beconfigured to manage and coordinate the overall operation of the storageand retrieval system 100 and interface with, for example, a warehousemanagement system 125, which in turn manages the warehouse facility as awhole. The control server 120 may be substantially similar to thatdescribed in, for example, U.S. patent application Ser. No. 12/757,337,entitled “CONTROL SYSTEM FOR STORAGE AND RETRIEVAL SYSTEMS” and filed onApr. 9, 2010, the disclosure of which is incorporated by referenceherein in its entirety.

Referring now to FIGS. 2A and 2B, each of the bots 110 in the storageand retrieval system 100 include one or more suitable electricitystorage devices for powering the bot 110. In the embodiments the one ormore electricity storage devices may be one or more suitable capacitorsor ultra-capacitors (referred to herein generally as capacitor 110C).While the embodiments are described with respect to capacitors it shouldbe understood that the electrical storage devices, in alternateembodiments, may be any suitable solid state, chemical, or otherelectricity storage system. Still, the bots may be powered by fossilfuels the replenishing of which may be substantially similar to thatdescribed herein.

To enable substantially full (about 100%) bot utility during normaloperation (e.g. when the bot is actively transferring items in thestorage and retrieval system) or during extended idle time, the bots oneach storage level 261-264 of the storage and retrieval system 100 mayrecharge or replenish their power supplies, such as the one or morecapacitors 110C, at charging locations or stations 290 at the multilevelvertical conveyor 150 exchange areas (e.g. bot/transfer stations 140).The bots may access the bot stations 140 by, for example, followinglines or other suitable guides, such as conveyor access guide lines130C1-130C3 on the transfer deck 130B. For example, the transfer deck130B may have any suitable number of travel guide lines 130L1-130L4 andany suitable number of shunt or bypass guide lines 130S1-130S7 that formone or more travel paths or lanes for the bots 110 to traverse. Forexample, guide lines 130L1, 130L2 allow travel in a first direction andguide lines 130L3, 130L4 allow travel in a second directionsubstantially opposite the first direction. The shunt guide lines130S1-130S7 may be oriented substantially transverse to the travel guidelines 130L1-130L4 but in other aspects they may have any suitableorientation relative to the travel guide lines. The shunt guide lines130S1-130S7 allow bidirectional travel of the bots 110 for switchingbetween travel guide lines 130L1-130L4 so that the bots can access, forexample, the picking aisles 130A or the bot stations 140 withouttraversing an entire length of the travel guide lines 130L1-130L4. Inthe embodiments, the shunt guide lines may be aligned with the pickingaisles 130A1-130A7 or any other suitable ingress or egress location ofthe storage and retrieval system allowing the bot to turn down acorresponding picking aisle while travelling along any one of the travelguide lines 130L1-130L4. The shunt guide lines 130S1-130S7 may also belocated at ends of the transfer deck 130B or at any other suitablelocations of the transfer deck 130B. As an example, a bot 110 travellingalong a path corresponding to guide line 130L1 may be instructed totransfer an item to a storage location in picking aisle 130A4. However,the bot 110 may have already passed the shunt guide line 130S4corresponding to picking aisle 130A4. The bot may continue to travelalong guide line 130L1 until it encounters the next available shunt(e.g. a shunt not being used by another bot) such as shunt guide line130S5. The bot may turn onto shunt guide line 130S5 and then turn ontoone of the guide lines 130L3, 130L4 so that the bot 110 is travelling insubstantially the opposite direction towards the picking aisle 130A4.The bot may continue to travel along one of the guide lines 130L3, 130L4until it encounters shunt guide line 130S4, corresponding to pickingaisle 130A4, where the bot turns onto shunt guide line 130S4 fortransitioning into or otherwise entering the picking aisle 130A4 guideway (such as, for example, a rail guidance system). The conveyor accessguide lines 130C1-130C3 may be substantially similar to the shunt guidelines 130S1-130S2 however, in the embodiments the conveyor access guidelines may only allow unidirectional travel of the bots 110 through thebot station 140. For example, conveyor access guide line 130C1 mayprovide an entrance path into the bot station. Conveyor access guideline 130C2 may provide a pathway for charging the bots 110 and allowingthe bots to interface with the multilevel vertical conveyor shelves 250.Conveyor access guide line 130C3 may provide an exit path into the botstation. The conveyor access guide lines 130C1-130C3 may also providebidirectional travel of the bots so that the bots 110 can enter and/orleave the bot station using either of guide lines 130C1 or 130C3. Theconveyor access guide lines 130C1, 130C3 may extend across the transferdeck 130B so that the bots can access the bot station 140 from any oneof the travel guide lines 130L1-130L4 and exit onto any one of thetravel guide lines 130L1-130L4 from the bot station 140. It is notedthat while the embodiments of the transfer deck 130B and bot stations140 are described herein with respect to line following, the transferdeck 130B and bot stations 140 may be configured so that the bots areguided by any suitable rail system. In one example, the bots 110 mayenter and exit the picking aisles 130A and the bot stations 140 witheither a front end of the bot leading the direction of travel or a backend of the bot leading the direction of travel as described in forexample, U.S. Provisional Patent Application Ser. No. 61/423,409entitled “AUTONOMOUS TRANSPORT VEHICLE” filed on Dec. 15, 2010 (now U.S.patent application Ser. No. 13/326,423 filed on Dec. 15, 2011), thedisclosures of which are incorporated herein by reference in theirentireties.

In the embodiments, the travel guide lines 130L1-130L4 and shunt guidelines 130S1-130S7 (including guide lines 130C1, 130C3) are arranged sothat the bots 110 travel in a substantially counterclockwise directionbut it should be realized that the guide lines may be arranged so thatthe bots travel in a substantially clockwise direction. When traversingthe guide lines 130L1-130L4, 130S1-130S7 collisions between the bots 110may be avoided in any suitable manner such as through bot-to-botcommunications or bot location tracking and management through, forexample, control server 120 or other suitable bot controller. A suitableexample, of bot collision avoidance may be found in, for example, U.S.patent application Ser. No. 12/257,337 entitled “CONTROL SYSTEM FORSTORAGE AND RETRIEVAL SYSTEMS” and filed on Apr. 9, 2010, the disclosureof which is incorporated by reference herein in its entirety.

In the embodiments the bot station 140 may be in the form of a vestibule130V that extends between the transfer deck 130B and the multilevelvertical conveyor 150. Each vestibule 130V may be configured with morethan one charging station 290A, 290B (each of which may also serve as atransfer location for accessing a respective portion of the multilevelvertical conveyor shelf 250) arranged in, for example, a linear array,along guide line 130C2. In this example, there are two charging stations290A, 290B corresponding with two item holding locations on themultilevel vertical conveyor shelf 250. It is noted that in theembodiments there may be any suitable number of charging stations, whichmay correspond with a respective number of item holding locations on themultilevel vertical conveyor storage shelf 250.

The charging stations 290A, 290B of each vestibule 130V may be connectedto a common power supply 290P as will be described in greater detailbelow. The common power supply 290P may power the charging stations 290of multiple bot stations 140. For example, the bot stations 140 may bedisposed one above the other in a vertical array or stack so that thebots 110 of each pick floor level 261-264 travel along substantiallyparallel paths while in the bot stations 140. The storage and retrievalsystem may include one or more power supplies 290P each of which may beconnected to the charging stations 290 of one or more pick floor levels261-264. Bot 110 ingress and egress to/from the vestibule 130V of thebot station 140 and to the charging stations 290 along, for example, theguide line 130C2 may be synchronized with other bots 110 destined for,leaving, or charging at the charging stations 290 by anaccess-charge-depart protocol, hosted in any suitable controller of thestorage and retrieval system, to maximize substantially full utility ofall charging stations 290 of a given vestibule 130V (e.g. tosubstantially avoid a case where the charging of bots 110 interfereswith the ingress/egress process or other bots 110 designated to travelto the same vestibule 130V). Each multilevel vertical conveyor may haveany suitable controller 150C, such as a programmable logic controller,for controlling the operations of the respective multilevel verticalconveyor 150 as well as controlling the power supply or supplies of thecharging stations 290 disposed on the vestibules 130V providing accessto the shelves 250 of the respective multilevel vertical conveyor 150.

The ingress and egress of the bots 110 to the vestibules 130V may bemanaged by, for example a level manager 297 a portion of which mayinclude a vestibule manager 296 (FIG. 10). The level manager 297 mayhave any suitable organization so as to, for example, manage botoperations on one or more pick floor levels, in one or more stacks ofbot stations 140 (e.g. bot stations 140 located one above the other), orin geographical regions of the storage and retrieval system. The levelmanager 297 may be in communication with the bots 110 in any suitablemanner using any suitable communication protocol. For example thecommunication between the bots 110 and the level manager 297 may be awired or wireless bidirectional and/or unidirectional communications,Linux based communications, etc. In the embodiments each pick floorlevel 261-264 may have its own respective level manager 297 forcontrolling or otherwise managing movement of the bots 110 on therespective level and/or, one level manager may manage more than one pickfloor level 261-264. The level manager 297 may be configured such thatit tracks the location of operative bot charging stations 290 andcommunicates with a gang manager 290G (FIG. 2B—described below) forobtaining access to the chargers and the status of bot 110 charges. Thevestibule manager 296 may manage the areas in which the chargingstations 290 are located for determining if access is available before,for example, the gang manager 290G requests access to the chargingstations. As will be described below, if one or more charging station290 in a vestibule is inoperative the vestibule manager 296 may, in theembodiments, close the vestibule (e.g. deny access so that bots aredirected to other vestibules) with the inoperative charging station(s)290.

Each bot 110, through any suitable onboard controller or manager, maycommunicate with the level manager to effect a charge cycle on the bot110 in combination with a case unit 101 exchange with a multilevelvertical conveyor 150 on the pick floor level 261-264 on which the bot110 is located. Each charging station 290A, 290B includes contacts 290Cfor interfacing with corresponding contacts 110D (e.g. such as a chargerpad) on the bot 110 for charging, for example, the bot's capacitor(s)110C. The contacts 290C may be any suitable contacts such as springloaded or other actuable contacts that are configured to engage thecontacts 110D of the bot 110 when the bot is positioned substantiallyover the charging station 290A, 290B. These charging station contacts290C may be positioned at the charging stations 290A, 290B such thatthey interface with the contacts 110D of a bot 110 when the bot 110 ispositioned for interface and exchange with one of the holding locationsof the multilevel vertical conveyor shelf 250. As described above thebots access the vestibules 130V of the bot stations 140 through anaccess-charge-depart protocol that may include getting permission totravel on to the charger contacts 290C (prior to item exchange with themultilevel vertical conveyor), initiating charge, and getting permissionto leave (after item exchange with the multilevel vertical conveyor).The level manager 297 may be configured to manage the requests foraccess to the vestibules 130V and charging stations 290A, 290B and makedecisions on whether to allow bots 110 to enter, leave andinitiate/terminate charging accordingly. A charge can be initiated oncethe bot 110 has gained access and stops on one of the charging stations290A, 290B corresponding to a location on the shelf 250 the bot 110 isto pick/place an item. The charging of the bot 110 may occur during thetime it takes to transfer an item between the bot 110 and the shelf 250or after the transfer has completed. In addition, the bot 110 may chargeat the nearest available (e.g. unallocated) vestibule 130V withoutinterfering with other transfers (non-determinative, opportunitycharging).

In the embodiments, the bots 110 may perform a quick charge beforeleaving the multilevel vertical conveyor vestibule 130V, at which pointthe multilevel vertical conveyor controller 150C may inform a gangmanager 290G (FIG. 2B) that a quick charge has been achieved. The quickcharge of the bot 110 may be a charge that terminates (or signals readyfor termination) at the point where the power supply 290P switches froma constant current mode (e.g. the power supply is delivering maximumcurrent output with variable voltage) to a constant voltage mode (e.g.where the power supply has reached the maximum voltage output set pointwith a variable current). It is noted that the bot 110 may remain at thecharging station 290A, 290B and continue to charge (e.g. to achieve atop off or full charge) until, for example the control server 120 orother suitable controller of the storage and retrieval system deemsnecessary to move the bot 110, such as to allow another bot 110 accessto the charging stations 290A, 290B.

During a quick charge the capacitor 110C of the bot 110 may be at avoltage that does not take into account losses from the power supply290P to the capacitor 110C. During a top off or full charge the extendedperiod for the capacitor to reach the applied voltage level (Tau=R*C,5*Tau≈99.3% of final voltage, where R is the combined ESR of thecapacitor and any resistance between the power supply sense lines (FIG.3) and the capacitor). The gang manager 290G may be a collection ofcooperating interfaces that manages gang charging of bots 110 (e.g.charging more than one bot at a time where a gang is a group of botsthat are charged by the same power supply) on multiple pick floor levels261-264 that share a power supply. In the embodiments there may be onegang manager 290G per power supply 290 or each gang manager may servemultiple power supplies. In the embodiments, the bots 110 may not haveaccess to a charging station 290 if the power supply 290P is enabled andoperational (e.g. power is being transferred to the charging stationwaiting to be accessed). In the embodiments, after charging and thepower supply 290P stops transmitting power to the charging station 290the gang manager 290G, for example, may cause the bot 110 to remain atthe charging station 290 for a predetermined amount of time, which inone example, may be about 280 milliseconds. In other examples, theamount of time the bot 110 remains at the charging station 290 after thepower is turned off may be any suitable time period.

Referring to FIGS. 3 and 4, there may be, for example, four chargingstations 290A, 290B, 290A2, 290B2 per power supply 290P. The chargingstations 290A, 290B, 290A2, 290B2 may be vertically placed within asingle multilevel vertical conveyor 150 area and disposed in arectangular configuration with two charging stations 290A, 290B on onepick floor level and two charging stations 290A2, 290B2 on anotherdifferent pick floor level, where the pick floor levels may be adjacentto one another. As an example, referring back to FIG. 2A, in this powersupply configuration the charging stations of pick floor levels 261, 262would share a power supply, the charging stations of pick floor levels263, 264 would share a power supply, etc. It is noted that in theembodiments there may be any suitable number of charging stations oneach pick floor level that share a power supply with any suitable numberof charging stations from one or more other pick floor levels. Eachpower supply 290P may be located within a predetermined distance to thecharging stations 290 that it serves. For example, power supply 290P maybe located less than about 18 feet from the charging stations 290A,290B, 290A2, 290B2 to, for example, reduce wiring loss and increasecharging throughput. It is noted that in the embodiments, the powersupplies 290P may be located any suitable distance from their respectivecharging stations 290.

As described above, each power supply may be controlled by, for example,a controller 150C of a respective multilevel vertical conveyor 150, orany other suitable controller. In the embodiments there can be up toabout sixteen power supplies 290 and up to about sixty-four chargingstations 290 associated with a single multilevel vertical conveyor 150where the charging stations are located on different pick floor levels.In the embodiments, the controller 150C may be configured such that whenthe multilevel vertical conveyor is stopped (e.g. power is shut off tothe conveyor) the charging stations 290 will remain operational. Powerto the charging stations 290 and the multilevel vertical conveyor may beindividually disabled/enabled.

Referring to FIGS. 2B and 3, and with respect to pick floor level 262for exemplary purposes, the bot charging process may initiated beforethe bot 110 enters the multilevel vertical conveyor area (e.g. the botstation 140). The bot may initiate communication with the gang manager290G to request permission to drive on to a particular charging station290A, 290B. In the embodiments, the decision on which charging station290A, 290B the bot is to interface with may be dependent on whichmultilevel vertical conveyor shelf 250 is the intended target and inwhich location of the shelf 250 the item to be transferred is to bepicked from or placed to.

The Bot may remain out of the charging station 290A, 290B area (e.g. theload/unload area of the multilevel vertical conveyor) until it receivespermission from, for example, the control server 120 (or other suitablecontroller such as the vestibule manager of the level manager) that itis safe to enter the charging station 290A, 290B. In one example, thegang manager 290G may have knowledge of any other bots 110 on the pickfloor level (which in this example is pick floor 262) that may accessthe charging station 290A, 290B and may command controller 150C to turnoff the power supply 290P for allowing a bot 110 to enter the chargingstation 290A, 290B. In one example, the gang manager 290G may have thediscretion to decide when to turn off the power supply 290P and when toallow the bot 110 on to the charging station 290A, 290B.

Once the Bot has permission to move in to the charging station 290A,290B (e.g. the multilevel vertical conveyor load/unload area), the bot110 may maneuver to the intended charging station 290A, 290B and reportits position accordingly. Once the bot 110 is located at the intendedcharging station 290A, 290B, the gang manager 290G may communicate tothe controller 150C to re-enable the power supply 290P, at which pointthe bot 110 will begin charging. This charging of the bot 110 mayoverlap with charging of other bots 110 that are on the same sharedcharging system network (e.g. if bot 110 is charging at charging station290A, other bots 110 may be also be charging at one or more of chargingstations 290B, 290A2, 290B2). In the embodiments, the charging processis open ended and may not terminate until commanded to do so by, forexample, the gang manager 290G or other suitable controller of thestorage and retrieval system 100.

The controller 150C may control the power supply 290P and monitor astatus of the power supply 290P. The controller 150 may monitor thestatus of the power supply 290P and report to, for example, the gangmanager 290G when the power supply 290P has reached a constant voltagemode and measures a current output falling below about 75% of itsmaximum value. It is noted that in the embodiments, the controller 150Cmay report to, for example, the gang manager 290G at any suitable timesuch as when the current output is above or below about 75%. At thispoint, the bot 110 has been “Quick Charged” and can be ready to performtasks as needed. The gang manager 290G may send a command to terminatethe charge cycle if the bot 110 is needed to transport items within thestorage and retrieval system 100. If the Bot is not needed, charging maycontinue and the charger supply may remain on indefinitely. It is notedthat in the embodiments the power to the charging station being used maybe shut off upon a predetermined condition such as when, for example,the bot reaches a “full charge.” A full charge may be accomplished ifthe Bot remains charging for about five R*C time constants. The time toreach a full charge may be dependent on, for example, such factorsincluding the resistance between the charger station contact 290C andthe contacts 110D of the bot 110, the wiring on the bot 110 as well asthe resistance inside the capacitor 110C. In one example, a bot 110 mayleave the charging station 290A, 290B any time after a quick charge.

In the embodiments there may be N number of gang managers 290Gcontrolling N number of power supplies 290P. For example, the controller150C of each multilevel vertical conveyor 150 may have addressable portsunique to each power supply 290P. The bot 110 when requesting a chargemay communicate, through for example, level manager 297 (FIG. 2B), witha gang manager 290G controlling a power supply 290P for a chargingstation to which the bot 110 will travel. As described above, thecommunication between the bots 110 and the level manager 297 as well asthe gang manager 290G, controller 150C and power supply 290P (and othersuitable components of the storage and retrieval system) may be anysuitable communication protocol and methods such as, for example, wiredor wireless bidirectional and/or unidirectional communications, Linuxbased communications, or other suitable communications.

Referring to FIG. 6, in the embodiments the level manager 297 may managethe bots 110 on a level (or more than one level) to which the levelmanager 297 is assigned. The level manager 297 may include a botcontroller 298 for use by the bots 110, and conversely each bot 110 mayinclude a controller 118 for use by the bot controller 298. There maybe, for example, a one to one mapping between the bot controller 298 andeach bot 110 (e.g. the level manager 297 includes one bot controller foreach bot) or, one bot controller may be mapped to more than one bot. Thelevel manager 297 may also include a charge manager 299 that may act asan intermediary between the bot controller 298 and the gang manager 290Gto manage charging.

Each bot controller 298 may communicate with the gang manager 290G viathe charge manager 299 to effect charging of the bot 110. In theembodiments there may be, for example, ten multilevel vertical conveyorsthat intersect the pick floor levels 261-264 (e.g. with twenty chargingstations 290 disposed at each pick floor level—e.g. two chargingstations per multilevel vertical conveyor intersection). It is notedthat in the embodiments there may be any suitable number of multilevelvertical conveyors and charging stations per pick floor level. Thecharge manager 299 may choose the appropriate charging station 290 toconverse with for a given charge cycle. Since bot gangs (e.g. groups ofbots charged using the same power supply) span adjacent levels, twolevel managers 297 may each establish communication connections with thecharging stations 290 of their respective levels (which in this example,is twenty charging stations per level).

Conversely, each charge manager 299 may include a charging stationstatus server 299S for each charging station 290, that the gang manager290G uses to relay power supply status information sent to it by acharging communication service 620. It is noted that the chargingcommunication service 620 may handle status requests from, for example,the controller 150C, on/off requests for, as an example, controller150C, and requests to enter/leave a charging station 290. Since eachgang manager 290G may manage two pick floor levels, it may haveconnections to, for exemplary purposes only, about four such chargingstation status server objects, e.g. two for each pick floor level. Theremay be as many named instances for requests to enter/leave a chargingstation 290 (e.g. a request instance) as there are charger stations 290.In one example, each group of four request instances maps to a portionof the charging communication service that handles on/off requests, andhosts a portion of the charging communication service that handlescharging station status requests.

In an exemplary operation, the bot controller 298 may issue tasks forthe bot 110. It is noted that when issuing tasks for the 110, the botcontroller 298 may allow for an efficient exchange of items between thebots 110 and the multilevel vertical conveyors. When issuing these tasksthe bot controller 298 may do so such that bots 110 are not held up fromentering the bot stations 140 (and charging areas 290) for commencingitem transfer with the multilevel vertical conveyor 150. Also, whenissuing tasks the bot controller may not prevent egress of bots from thecharging areas 290 because of bots 110 that have not finished chargingor have not received a minimum amount of charge. It is also noted thatif a first bot 110 has not completed a case unit 101 transfer with themultilevel vertical conveyor 150 any bots located in charging stations290 behind the first bot 110 may remain in their charging stations tocontinue receiving a charge.

Referring to FIG. 7, when issuing tasks the bot controller may be awareof when the bot 110 needs to enter the charging station 290, and whenthe bot 110 is at the charging station 290. However, the bot controller298 may not be aware of exactly when in time the bot 110 clears orleaves the charging station 290. The bot controller 298 and the bot 110may cooperate with each other to create a charging cycle. In anexemplary charging cycle, the bot controller may identify theappropriate charging station 290 to communicate with. The bot controller298 may request (e.g. a “can bot enter” message) that the charge manager299 send a “bot can enter” message to the charging station 290. The gangmanager 290G may verify that the charging station 290 is turned off andwaiting for a charger status to reflect the off status. The gang manager290G may send a charger status and “bot can enter” message to the chargemanager 299, which relays it to the bot controller 298. The botcontroller 298 may issue other tasks to the bot 110 via the controller118. When the bot 110 reaches the charging station 290, the botcontroller 298 may wait for a “bot is at charging station” message inorder to read a simulated bot voltage and ask the charge manager 299 tosend a “bot is at charging station” message to, for example the gangmanager 290G. The charge manager may send a “bot has quick charge”message when the bot 110 has received a quick charge. This allows thelevel manager 297 to mark the bot 110 as available for other tasks, whenit finishes any current job, such as the transfer of items between thebot 110 and the multilevel vertical conveyor. When the bot controller298 deems that the bot 110 should move out of the charging station 290,it asks the charge manager to send a “can bot leave” message, to forexample, the gang manager 290G. The gang manager 290G verifies that atleast a quick charge has been delivered to the bot 110, turns off thecharging station 290 if necessary, and sends a “bot can leave” message,which gets relayed to the bot controller 298 and then to the controller118. This allows the simulated bot to update its voltage at the end of acharge cycle. It is noted that the simulate bot may exist in the anysuitable memory of any suitable controller of the storage and retrievalsystem such that based on the tasks sent to the bot, the controller candetermine how much of a charge remains in the bot. It is noted that inthe embodiments, the bots 110 may periodically send a message to thecontroller indicating a charge status of the bots 110 or that the bots110 need to be charged. The bot controller 298 may send the next set oftasks to the bot 110. When the bot 110 deems that it is safely out ofthe charging area, the bot 110 may send a “bot has left” message, whichcauses the bot controller 298 to send a “bot has left” message via thecharge manager 299. The bot 110 need not wait for an acknowledgement orstop its motion to send this message. The power supply 290P getsre-enabled by the gang manager 290G if necessary for other botsremaining at the charger stations 290.

In the embodiments, separately from any ongoing charge cycleinteractions, the gang manager 290G may relay power supply statusinformation to, for example, the level manager 297 so that the levelmanager may route bots 110 away from unavailable chargers. It is notedthat the level manager 297 may establish, through for example, the gangmanager 290G the operational status of each of the charging stations 290and whether the charging stations 290 are available.

It is noted that each bot goes through the same charging sequencedescribed above. In the embodiments, the gang manager 290G may beconfigured to reconcile multiple pending charge requests by turning eachof the charging stations on and off, individually or in groups, asneeded. The gang manager may also be configured to collectively turn offthe charging stations by, for example, turning off the power supply290P. This is done by keeping track of the number of bots 110 movingto/from the charging stations 290, and the number of bots at thecharging stations 290. One non-limiting example, of keeping tracking ofbots 110 is as follows:

Request Actions Can Bot Enter If necessary, the charger is turned OFFWhen the charger is confirmed to be OFF:  iNumMoving++  Send botCanEnterBot Is At Contact iNumMoving− iNumAt++ if(!iNumMoving &&iNumAt)turn_charger_on( ) Can Bot Leave If bot has not received onecharge cycle, defer request until such charge is received or powersupply fails or is disabled. Charger is turned OFF if necessary When thecharger is confirmed to be OFF:  iNumMoving++  Send botCanLeave Bot HasLeft iNumMoving− if (!iNumMoving && iNumAt) turnChargerOn( ) ChargerStatus If charger passed the quick charge mark, mark all bots at chargerto have received a quick charge so they can leave if desired. Send thebotHasQuickCharge( ) message. If charger turned off as a result ofhaving been turned off, update all bot states as outlined previously sobots can enter or leave the charger contact. If the charger had anerror, send notification on appropriateChargerContactStatus::isAvailable( ) interfaces.

The term “Comm Failure” may be used to indicate that the two sides of acommunication connection get an “unbind” indication. Conversely, the“bind” indication indicates a (re)connection between the two sides. Thefollowing outlines non-limiting exemplary charging specific actions thatmay be done upon various failures.

Activity Value Rationale Comm message About Expected worst case time fora comm transaction time 1 second message to reach destination Maximumpower About Power supply specification supply cutoff voltage 46.3 VPower supply turn About Hardware behaviour off time 2 seconds Powersupply About Power supply field configuration maximum current 110AHighest bot About The supercap used on the bots is capacitance 181.5 F.nominally about 165 F., allow 10% variation Maximum charge About Largestvoltage delta to quick time for a bot 305 charge seconds =MaxPowerSupplyCutoff - 0 V = about 46.3 V Smallest current whilecharging = Power supply minimum current/ MaxContactsPerSupply = 111/4 =about 27.25 A Worst case time to charge = max_capacitance * max_delta_V/min_current = 181.5 * 46.3/27.25 = about 303 seconds Additional about 2seconds to turn off supply at end. Time for bot to move X Allowance forbot to contact after seconds having received permission to do so Timefor bot to move Y Allowance for bot away from contact seconds afterhaving received permission to do so Overall margin About Additionalmargin for all timeout 10%, calculations minimum, about 1 second

The following are non-limiting exemplary timeout values that may be usedto deem a transaction to be a failure.

Time out Entity using Transaction (sec) timeout Rationale canBotEnterAbout 7 Charge Manager About 4 comm -> transactions turn botCanEnter offpower supply botCanEnter About 8 Gang Manager About 2 comm ->transactions move botIsAtContact bot act botIsAtCont About 338 ChargeManager About 2 comm act -> transactions to botHasQuick gang managerCharge Max charge time = N seconds canBotLeave About 7 Charge ManagerAbout 4 comm -> transactions turn botCanLeave charger off botCanLeaveAbout 6 Gang Manager Move bot -> botHasLeft Time to About 5 Gang Manageroff cycle turn off a About 1 each for bot comm Time to About 338 GangManager About 2 comm charge a transactions max bot charge time = Nseconds

When there is a power supply failure a message may be relayed from thegang manager 290G. During a power supply failure the bots 110 may beallowed to leave the charging stations 290 even if the bots have notreceived a minimum amount of charge. The charge manager 299 may use theinformation from the gang manager 290G in conjunction with, for example,the state of the bot 110 or bot controller's 298 conversation with thegang manager 290G to complete any pending charging cycles, and mark thecharging station(s) 290 connected to the failed power supply asinoperable. In this case the gang manager 290G and or charger manager299 may find other available charging stations 290 and communicate withthe level manager 297 for routing the bots 110 that did not receive theminimum amount of charge to these available charging stations 290 (e.g.without impeding ingress/egress to the respective multilevel verticalconveyors 150 at the locations of the available charging stations 290.

With respect to other exemplary communications within the bot chargingsystem, the bots 110 may communicate with a respective bot controller298 to indicate a simulated bot's voltage and that the bot has left (orarrived at) a charging station 290. The bot controller 298 maycommunicate with a respective bot 110 a post-charge voltage that may bevalid only during a simulation. The charge manager 299 may communicatewith the charging stations 290 to ensure the charging station is off soa bot 110 can enter or leave the charging station 290. The chargemanager 299 may also indicate when gang charging can start or resume,indicate that a bot has left a charging station and to resume chargingand to enable/disable one or more charging stations. The gang manager290G may indicate the charging station is off so that the bot can moveon to or off the charging station, that the bot has received a quickcharge, and a state of the charging station 290 (e.g. whether thecharging station is inoperable, off, in constant current mode, inconstant voltage mode, etc.).

In the embodiments, the bot controller 298 may be configured to allocatethe charging stations 290 using reservations (e.g. each bot that is toaccess a particular charging station “reserves” or allocates thatcharging station so no other bots are able to access it during thereservation period). When a bot 110 with a reservation accesses acharging station 290 it receives a charge and when complete the bot 110requests to release (e.g. un-reserve) the charging station 290 so thatthe charging station 290 can be reserved for other bots 110. FIG. 8illustrates a transaction state diagram for a charging sequence in whicha reservation is held. For example, before the bot enters the chargingstation 290 a request is made for the bot to enter the charging station.If there is no bot present at the charging station 290 the request maybe granted and the bot enters the charging station 290. If only atransfer of items to/from a multilevel vertical conveyor 150 is beingmade, the transfer may take place and a request for release of thecharging station 290 may be sent by the bot 110 and after the release anotification that the bot 110 has left may be made. Where charging is tooccur (in addition to or in lieu of a transfer of items to/from themultilevel vertical conveyor 150) charging may occur when the bot 110 isin the charging station 290. A check may be made as to whether the bot110 has received a quick charge. If the bot 110 has received a quickcharge the bot 110 is able to leave the charging station 290 and makes arequest to release the charging station 290. Once the charging station290 is released the bot 110 exits the charging station 290 and anindication that the bot 110 has left is made. FIG. 9 illustratesexemplary class hierarchies and dependencies with respect tocommunication between the charge manager 299 and the bots 110.

In the embodiments the operational state of the charging station withina vestibule 130V may be linked in any suitable manner to an operationalstate of a corresponding multilevel vertical conveyor 150. Referring toFIG. 10, for exemplary purposes only four vestibules 130V1-130V4 of asingle pick floor level are shown where each vestibule 130V1-130V4 hastwo charging stations 290. It is noted that in the embodiments thestorage and retrieval system may have any suitable number of vestibuleseach having any suitable number of charging stations. Each vestibule isserved by a respective multilevel vertical conveyor 150-1, 150-2, 150-3,150-4. Each of these multilevel vertical conveyors also serves othervestibules vertically stacked above and/or below a respective one of thevestibules 130V1-130V4.

Upon startup of the level manager 297, with respect to chargingoperations of the bots 110, the charge manager 299 knows the structuralinformation about each charging station 290 (e.g. where they are locatedand which multilevel vertical conveyor is associated with the respectivecharging stations). The charge manager 299 may communicate with eachcharging station 290 to obtain, for example, an operational status ofthe charging stations 290. The bot controller 298 of the level manager297 may communicate with the bots 110 for issuing commands or jobs (e.g.to transfer case units 101) to the bots 110.

When a bot, such as bot 110X, needs to be charged, whether inconjunction with the transfer of a case unit 101 to/from a multilevelvertical conveyor 150-1, 150-2, 150-3, 150-4 or not, the bot may send amessage to a vestibule manager 296 for determining which vestibule130V1-130V4 the bot is to be directed to. In the embodiments thevestibule manager 296 may be part of the level manager 297 or, thevestibule manager 296 may be included in any suitable controller of thestorage and retrieval system. If the charging of bot 110X is not inconnection with a case unit 101 transfer, the vestibule manager 296 maydirect the bot 110X to a vacant or unallocated operational chargingstation 290 in a nearest “online” or operational vestibule 130V1-130V4.If the charge of the bot 110X is in conjunction with a transfer of caseunits 101 to/from a multilevel vertical conveyor 150-1, 150-2, 150-3,150-4, the vestibule manager 296 may communicate with the vestibule(which for exemplary purposes may be vestibule 150-3) at which the bot110X is to transfer the case units 101 to verify that the chargingstations 290 of that vestibule are operational. At least one of thecharging stations at, for example, vestibule 150-3 may be reserved forthe bot 110X as described above. If however, one or more of the chargingstations for the vestibule 150-3 is determined as being inoperable asuitable controller of the storage and retrieval system such as controlserver 120 may inform the level manager 297 and/or the vestibule manager296 that the vestibule 150-3 is “offline” or inoperable such that nocase units 101 can be transferred to the multilevel vertical conveyor150-3 nor can bots 110 be charged at other operational charging stations290 of offline vestibule 130V3. The level manager 297, with informationprovided by the vestibule manager 296, may communicate with bot 110X anddirect the bot 110X to an available charging station 290 of the nextavailable vestibule 130V1-130V4 for transferring the item 101 whilesimultaneously charging the bot 110X.

In the embodiments, vestibules vertically stacked above and/or belowvestibule 130V3 may still be able to charge bots 110 and transfer caseunits 101 to the multilevel vertical conveyor 150-3. In the embodiments,because the charging stations 290 of vestibule 130V3 may be powered bythe same power supply 290P (FIG. 3) as charging stations of vestibulesstacked above and/or below vestibule 130V3, all of the vestibulesassociated with the power supply of vestibule 130V3 may be designated asoffline for charging and item 101 transfers. Still, the vestibule 130V3may remain “online” so that bots can charge and transfer case units 101at the remaining operational charging station(s) 290 of the vestibule130V3. The vestibule 130V3 may also remain online with respect to itemtransfers such that, if bot 110X has a sufficient charge, the bot 110Xcan transfer items at a location of the inoperable charging station 290and then move on to be charged at a next available charging station 290at the same vestibule 130V3 or different vestibule 130V1, 130V2, 130 V4.

Referring to FIGS. 11-13 and also to FIGS. 2B and 6 the bot controller298 and charge manager 299 may interact with each other for reservingresources within the storage and retrieval system 100. It is noted thatFIG. 12 illustrates a state chart diagram for bot controller 298interaction for reserving resources of the storage and retrieval systemand FIG. 13 illustrates a sequence diagram of how each reservationrequest for a charging station translates into a reservation of thecharging station. As an example, bot 110X may be designated by botcontroller 298 for charging at charging station 290B of vestibule 130V.Travel of the bot 110X may be defined by waypoints 1101-1108 within thestorage and retrieval system 100. As the bot travels the bot controller298 of level manager 297 may look to each waypoint for reserving aresource of the storage and retrieval system to allow the bot 110X totravel along a predetermined course. Prior to or during reservation ofthe resources by the bot controller 298 the charge manager may confirmthat a desired charging resource and any intervening charging resourcesare available or will be available at the time they are needed by thebot 110X. If the charging resources are available the bot controller 298continues with planning the predetermined route, which in this example,is charging station 290B. If one or more of the charging resources andintervening charging resources are not or will not be available theroute of the bot 110X may be re-routed to an available charging resource(and corresponding multilevel vertical conveyor). In this example, thebot 110X may start in picking aisle 130A7 for picking a case unit 101.Picking aisle 103A7 may be reserved by the bot 110X while the bot 110 islocated within the aisle 130A7. As the bot is travelling out of thepicking aisle 130A7 a request to reserve an entrance onto guide line ortravel path 130L4 is made and granted. Once on the guide line 130L4 areservation is requested for travelling along vestibule 130V/multilevelvertical conveyor 150 entrance guide line or path 130C1 and is granted.The bot controller looks to the next waypoint 1107 and requests areservation for the multilevel vertical conveyor transfer location 290T1and if the availability of the transfer location 290T1 is verified therequest is granted. The bot controller may check to see of the transferlocation 290T1 is also a charging resource, which it is, and requests areservation for charging station 290A and if the charging station isavailable the request is granted. Even though the bot 110X will nottransfer case units 101 or charge at transfer location 290T1/chargingstation 290A, the bot 110X passes through these areas on its way tocharging station 290B and reserves transfer location 290T1/chargingstation 290A to ensure passage to charging station 290B. The botcontroller also looks to waypoint 1108 to reserve multilevel verticalconveyor transfer location 290T2 and if the availability of the transferlocation 290T2 is verified the request is granted. The bot controller298 may check to see of the transfer location 290T2 is also a chargingresource, which it is, and requests a reservation for charging station290B and if the charging station is available the request is granted.After the bot passes through transfer location 290T1 and chargingstation 290A the bot controller releases transfer location 290T1 andcharging station 290A so these resources are available to other bots110. While the bot 110X is at the transfer location 290T2, the bot 110Xmay transfer case units 101 between the bot 110X and the conveyor shelf250 while simultaneously receiving a charge from charging station 290B.Upon reaching a quick charge level the bot 110X the bot controller 298is notified of the quick charge being substantially complete andrequests that the bot 110X leave the transfer location 290T2 andcharging station 290B. The bot 110X verifies that it has left thetransfer location 290T2 and charging station 290B and the bot controllerreleases the transfer location 290T2 and charging station 290B so theybecome available resources for other bots 110.

Referring again to FIGS. 6 and 10, as described above, when a chargingstation 290 becomes inoperable the storage and retrieval system isconfigured to re-route a bot 110 to another operable charging station290. In one exemplary embodiment when a charging station 290 becomesinoperable all affected bot controllers 298 are notified for takingappropriate action such as, for example, canceling jobs directed to theinoperable charging station. It is noted that in one exemplaryembodiment the affected bot controller 298 may be bot controller forpick floor levels having charging stations powered by the same powersupply as the inoperable charging station. Any bot jobs not yetscheduled (e.g. that have already been re-routed) may not be allocatedto the inoperable charging stations 290 or their correspondingmultilevel vertical conveyors 150 for at least the pick floor level onwhich the inoperable charging station 290 is located.

Referring again to FIG. 2B in the embodiments the controller 150C may beused to initiate and monitor charging of the bots 110. In one examplethe gang manager 290G may start the power supply 290P and the controller150C may enable the power supply output. The controller 150C may monitoran operational status of the power supply and alert the gang manager290G if there is any inoperability of the power supply 290P. Thecontroller 150C may wait a predetermined amount of time beforemonitoring the power supply 290P (e.g. to avoid any inrush power spikes)and maintain a record of the current of the power supply and monitorsthe current for a condition where the current drops below apredetermined level. The gang manager 290G may turn off the power supplyfor any suitable reason (such as e.g. when a bot wants to enter or leavea charging station) and the controller 150C may turn off the power tothe chargers and direct the bots 110 accordingly.

In a first aspect of the embodiments, a charging system for autonomoustransport vehicles in a warehouse storage and retrieval system isprovided. The charging system includes at least one charging contactdisposed on each pick floor level of the storage and retrieval system,each of the at least one charging contact being located at a transferstation, at least one power supply configured to supply power to the atleast one charging contact and a first controller in communication withthe transfer station and being configured to communicate informationrelating to a transfer of items between the transfer station and apredetermined one of the autonomous transport vehicles and to applypower from the power supply to the at least one charging contact forcharging the predetermined autonomous transport vehicle corresponding tothe transfer and located at the multilevel vertical conveyor transferstation, wherein the first controller is configured to supply power tothe charging contacts for charging the predetermined autonomoustransport vehicle simultaneously with the predetermined autonomoustransport vehicle exchanging items at the transfer station.

In accordance with a first sub-aspect of the first aspect of theembodiments, the charging system further comprising a capacitor disposedon the autonomous transport vehicle and a receptacle configured tointerface with the at least one charging contact where the engagement isconfigured to transfer power to the capacitor.

In accordance with the first sub-aspect of the first aspect of theembodiments, the receptacle includes a contact pad and the at least onecharging contact includes actuable members configured to engage thecontact pad.

In accordance with the first aspect of the embodiments, each pick floorof the storage and retrieval system includes at least one vestibuleextending from a transfer deck and located adjacent a respectivemultilevel vertical conveyor, wherein at least one charging contact islocated in each of the at least one vestibule.

In accordance with the first aspect of the embodiments, the transferstation includes a multilevel vertical conveyors and the operation ofthe at least one charging contact and an associated multilevel verticalconveyor are linked such that when the at least one charging contact isinoperable the controller deems the multilevel vertical conveyorinoperable at least for the pick floor level on which the at least onecharging contact is located.

In accordance with the first aspect of the embodiments, the firstcontroller is configured to control operations of the power supply andthe multilevel vertical conveyor.

In accordance with a second sub-aspect of the first aspect of theembodiments, the charging system further comprises a second controllerconfigured to effect a charge cycle of each autonomous transport vehiclelocated on at least one pick floor level simultaneously with theexchange of items with the multilevel vertical conveyor.

In accordance with a second aspect of the embodiments, a storage andretrieval system is provided. The storage and retrieval system includes,at least one autonomous transport vehicle, at least one transfer stationhaving an operable and inoperable state where in the operable state theat least one transfer station is configured to allow transfer of itemsfrom and to the at least one autonomous transport vehicle, at least onecharging station disposed on each pick floor level of the storage andretrieval system, each of the at least one charging contact beinglocated at a respective one of the at least one transfer station, atleast one power supply configured to supply power to the at least onecharging contact, and a controller in communication with the transferstation and being configured to communicate information relating to atransfer of items between the transfer station and a predetermined oneof the autonomous transport vehicles and to apply power from the powersupply to the at least one charging station for charging the at leastone autonomous transport vehicle located at the transfer station,wherein the controller is configured to supply power to the chargingstation for charging a predetermined autonomous transport vehiclecorresponding to the transfer of items simultaneously with thepredetermined autonomous transport vehicle exchanging items related tothe transfer at a predetermined transfer station when the predeterminedtransfer station is in the operative state and to supply power to thecharging station for charging another of the at least one autonomousvehicles located at the predetermined transfer station when thepredetermined transfer station is in the inoperative state.

In accordance with the second aspect of the embodiments, the storage andretrieval system further includes at least one multilevel conveyor andat least one pickfloor level having storage locations, at least onevestibule and a transfer deck connecting the storage locations with theat least one vestibule, each of the at least one vestibules having atleast one of the at least one transfer station configured to provideaccess to a respective one of the at least one multilevel verticalconveyor, wherein the controller is configured to control operations ofat least one of the at least one multilevel vertical conveyors andoperations of at least one charging station located in vestibulesassociated with the respective multilevel vertical conveyor.

In accordance with the second aspect of the embodiments, a levelcontroller is connected to each pick floor level and configured tocontrol storage and retrieval operations of the respective level, thelevel controller being further configured to link operations of the atleast one multilevel vertical conveyors with associated chargingstations such that access to the at least one multilevel verticalconveyor is prevented when one or more of the associated chargingstations is inoperable.

In accordance with a first sub-aspect of the second aspect of theembodiments, the storage and retrieval system includes at least onepower supply, the at least one power supply being commonly connected tocharging stations of vertically adjacent ones of the at least one pickfloor level.

In accordance with the first sub-aspect of the second aspect of theembodiments, the charging stations commonly connected to the at leastone power supply comprising a two by two array of charging stationswhere a first two of the charging stations in the array are located on afirst pick floor level and a second two of the charging stations in thearray are located on a second pick floor level, the first two of thecharging stations and the second two of the charging stations beingvertically stacked one above the other.

In accordance with the first sub-aspect of the second aspect of theembodiments, each vestibule includes at least two charging stationsarranged on a common linear path.

In accordance with the first sub-aspect of the second aspect of theembodiments, the transfer deck includes an array of autonomous transportvehicle travel paths, the array including longitudinal travel pathsproviding access to the storage locations and the at least one vestibuleand transverse travel paths providing shunts between the longitudinaltravel paths.

In accordance with the second sub-aspect of the second aspect of theembodiments, the controller is configured to reserve one or more of thecharging stations for allowing an autonomous transport vehicle access tothe one or more of the at least two charging stations.

In accordance with the second aspect of the embodiments, the controlleris configured to re-route an autonomous transport vehicle destined for acharging station at a first vestibule to a charging station at anothervestibule when the charging station at the first vestibule isinoperable.

In accordance with the second aspect of the embodiments, when in theunallocated state the transfer station is not configured to allowtransfer of items from and to the at least one autonomous transportvehicle.

It should be understood that the embodiments disclosed herein can beused individually or in any suitable combination thereof. It should alsobe understood that the foregoing description is only illustrative of theembodiments. Various alternatives and modifications can be devised bythose skilled in the art without departing from the embodiments.Accordingly, the present embodiments are intended to embrace all suchalternatives, modifications and variances that fall within the scope ofthe appended claims.

What is claimed is:
 1. A method comprising: providing at least oneautonomous transport vehicle; providing at least one transfer stationhaving an allocated and unallocated state where in the allocated statethe at least one transfer station allows transfer of items from and tothe at least one autonomous transport vehicle; providing at least onecharging station on each pick floor level of a storage and retrievalsystem, each of the at least one charging station being located at arespective one of the at least one transfer station; providing at leastone power supply configured to supply power to the at least one chargingstation; communicating, with a controller in communication with at leastone of the at least one charging station or the at least one autonomoustransport vehicle, information related to a transfer of items between apredetermined at least one transfer station and a predetermined one ofthe at least one autonomous transport vehicle; and with the controller,applying power from the at least one power supply to the at least onecharging station for charging the at least one autonomous transportvehicle located at the at least one transfer station, wherein thecontroller supplies power to the at least one charging station forcharging the predetermined one of the at least one autonomous transportvehicle corresponding to the transfer of items with the predeterminedone of the at least one autonomous transport vehicle transferring theitems at the predetermined at least one transfer station with thepredetermined at least one transfer station in the allocated state andidentifying an unallocated time period with the predetermined at leastone transfer station in the unallocated state and a next allocated timeperiod for another one of the at least one autonomous transport vehicleat the at least one charging station of the predetermined at least onetransfer station and continuous charging of the at least one autonomoustransport vehicle in the unallocated state.
 2. The method of claim 1,further comprising effecting, with the controller, at least one of aquick charge and a full charge to both the predetermined one of the atleast one autonomous transport vehicle corresponding to the transfer ofitems with the predetermined one of the at least one autonomoustransport vehicle transferring the items at the predetermined at leastone transfer station when the predetermined transfer station is in theallocated state, and an idle autonomous transport vehicle at the atleast one charging station when the predetermined at least one transferstation is in the unallocated state wherein the full charge is effectedwith the at least one autonomous transport vehicle at the at least onecharging station during the allocated state and remaining at least partof the unallocated state and the quick charge is effected ondetermination by the controller that a time period of the allocatedstate and unallocated state of the predetermined at least one transferstation is less than a charge period for full charge.
 3. The method ofclaim 1, wherein the at least one power supply is commonly connected tothe at least one charging station of vertically adjacent ones of the atleast one pick floor level.
 4. The method of claim 3, wherein the atleast one charging station is commonly connected to the at least onepower supply comprising a two by two array of charging stations where afirst two of the charging stations in the array are located on a firstpick floor level of the at least one pick floor level and a second twoof the charging stations in the array are located on a second pick floorlevel of the at least one pick floor level, the first two of thecharging stations and the second two of the charging stations beingvertically stacked one above the other.
 5. The method of claim 1,further comprising reserving, with the controller, access to one or moreof the at least one charging station by one of the at least oneautonomous transport vehicles.
 6. The method of claim 1, furthercomprising re-routing, with the controller, one of the at least oneautonomous transport vehicles destined for a first charging station, ofthe at least one charging station, to a second charging station, of theat least one charging station, when the first charging station isinoperable.
 7. The method of claim 1, wherein the at least one transferstation includes a lift and operation of the at least one chargingstation and an associated lift are linked such that when the at leastone charging station is inoperable the controller deems the associatedlift inoperable at least for the pick floor level on which the at leastone charging station is located.
 8. A method comprising: providing atleast one autonomous transport vehicle; providing at least one transferstation having an allocated and unallocated state where in the allocatedstate the at least one transfer station allows transfer of items fromand to the at least one autonomous transport vehicle; providing at leastone charging station on each of at least one pick floor level of astorage and retrieval system, each of the at least one charging stationbeing located at a respective one of the at least one transfer station;providing at least one power supply configured to supply power to the atleast one charging station; communicating, with a controller incommunication with at least one of the at least one charging station andthe at least one autonomous transport vehicle, information related to atransfer of items between the at least one transfer station and apredetermined one of the at least one autonomous transport vehicle; andapplying power, with the controller, from the power supply to the atleast one charging station for charging the at least one autonomoustransport vehicle located at the at least one transfer station, whereinthe controller is configured to supply power to the at least onecharging station to effect at least one of a quick charge and a fullcharge depending on identification of an unallocated time period of theat least one transfer station in the unallocated state.
 9. The method ofclaim 8, wherein each of the at least one pick floor level includes atransfer deck and a picking aisle in communication with the at least onecharging station.
 10. The method of claim 9, further comprisingcommunicating with an idle autonomous transport vehicle on one of thetransfer deck and the picking aisle, with the controller, andidentifying a nearest available transfer station, of the at least onetransfer station, in the unallocated state for charging the idleautonomous transport vehicle at the at least one charging station of thenearest available transfer station, of the predetermined at least onecharging station, in the unallocated state.
 11. The method of claim 8,wherein the at least one power supply is commonly connected to the atleast one charging station of vertically adjacent ones of the at leastone pick floor level.
 12. The method of claim 11, wherein the at leastone charging station is commonly connected to the at least one powersupply comprising a two by two array of charging stations where a firsttwo of the charging stations in the array are located on a first pickfloor level of the at least one pick floor level and a second two of thecharging stations in the array are located on a second pick floor levelof the at least one pick floor level, the first two of the chargingstations and the second two of the charging stations being verticallystacked one above the other.
 13. The method of claim 8, furthercomprising reserving, with the controller, access to at least one of theat least one charging station by one of the at least one autonomoustransport vehicles.
 14. The method of claim 8, further comprisingre-routing, with the controller, one of the at least one autonomoustransport vehicles destined for a first charging station, of the atleast one charging station, to a second charging station, of the atleast one charging station, when the first charging station isinoperable.
 15. A warehouse storage and retrieval system comprising: atleast one autonomous transport vehicle; at least one transfer stationhaving an allocated and unallocated state where in the allocated statethe at least one transfer station allows transfer of items from and tothe at least one autonomous transport vehicle; at least one chargingstation disposed on each of at least one pick floor level of thewarehouse storage and retrieval system, each of the at least onecharging station being located at each respective one of the at leastone transfer station and each of the at least one pick floor levelincluding a transfer deck and a picking aisle in communication with theat least one charging station; at least one power supply configured tosupply power to the at least one charging station; and a controller incommunication with at least one of the at least one charging station andthe at least one autonomous transport vehicle, where the controller isconfigured to communicate information related to a transfer of itemsbetween a predetermined at least one transfer station, of the at leastone transfer station, and a predetermined one of the at least oneautonomous transport vehicle, apply power from the at least one powersupply to the at least one charging station for charging the at leastone autonomous transport vehicle located at the at least one transferstation, wherein the controller supplies power to the at least onecharging station to effect at least one of a quick charge and a fullcharge depending on identification of an unallocated time period of theat least one transfer station in the unallocated state.
 16. Thewarehouse storage and retrieval system of claim 15, wherein thecontroller is configured to effect at least one of a quick charge and afull charge to both the predetermined one of the at least one autonomoustransport vehicle corresponding to the transfer of items with thepredetermined one of the at least one autonomous transport vehicletransferring the items at the predetermined at least one transferstation when the predetermined at least one transfer station is in theallocated state, and an idle automated transport vehicle at the at leastone charging station when the predetermined at least one transferstation is in the unallocated state.
 17. The warehouse storage andretrieval system of claim 15, wherein the at least one power supply iscommonly connected to the at least one charging station of verticallyadjacent ones of the at least one pick floor level.
 18. The warehousestorage and retrieval system of claim 17, wherein the at least onecharging station is commonly connected to the at least one power supplycomprising a two by two array of charging stations where a first two ofthe charging stations in the array are located on a first pick floorlevel of the at least one pick floor level and a second two of thecharging stations in the array are located on a second pick floor levelof the at least one pick floor level, the first two of the chargingstations and the second two of the charging stations being verticallystacked one above the other.
 19. The warehouse storage and retrievalsystem of claim 15, wherein the controller is configured to access oneor more of the at least one charging station by one of the at least oneautonomous transport vehicles.
 20. The warehouse storage and retrievalsystem of claim 15, wherein the controller is configured to re-route oneof the at least one autonomous transport vehicle destined for a firstcharging station, of the at least one charging station, to a secondcharging station, of the at least one charging station, when the firstcharging station is inoperable.